8.0% Efficient all-polymer solar cells based on novel starburst polymer acceptors  

作　　者：Kang Li Ruihao Xie Wenkai Zhong Kaiwen Lin Lei Ying Fei Huang Yong Cao 

机构地区：[1]Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices,South China University of Technology

出　　处：《Science China Chemistry》2018年第5期576-583,共8页中国科学（化学英文版）

基　　金：supported by the Ministry of Science and Technology of China(2014CB643501);the National Natural Science Foundation of China(51673069,91633301,21520102006,21761132001);Foundation of Guangzhou Science and Technology Project(201707020019,201607020010);the Pearl River S&T Nova Program of Guangzhou(201710010021)

摘　　要：The polymer N2200, with its π-conjugated backbone composed of alternating naphthalene diimide(NDI) and bithiophene(DT)units, has been widely used as an acceptor for all-polymer solar cells(all-PSCs) owing to its high electron mobility and suitable ionization potential and electron affinity. Here, we developed two naphthalene diimide derivatives by modifying the molecular geometry of N2200 through the incorporation of a truxene unit as the core and NDI-DTas the branches. These starburst polymers exhibited absorption spectra and molecular orbital energy levels that were comparable to N2200. These copolymers were paired with the wide-bandgap polymer donor PTz BI-O to fabricate all-polymer solar cells(all-PSCs), which displayed impressive power conversion efficiencies up to 8.00%. The improved photovoltaic performances of all-PSCs based on these newly developed starburst acceptors can be ascribed to the combination of increased charge carrier mobilities, reduced bimolecular recombination, and formation of more favorable film morphology. These findings demonstrate that the construction of starburst polymer acceptors is a feasible strategy for the fabrication of high-performance all-PSCs.The polymer N2200, with its π-conjugated backbone composed of alternating naphthalene diimide（NDI） and bithiophene（DT）units, has been widely used as an acceptor for all-polymer solar cells（all-PSCs） owing to its high electron mobility and suitable ionization potential and electron affinity. Here, we developed two naphthalene diimide derivatives by modifying the molecular geometry of N2200 through the incorporation of a truxene unit as the core and NDI-DTas the branches. These starburst polymers exhibited absorption spectra and molecular orbital energy levels that were comparable to N2200. These copolymers were paired with the wide-bandgap polymer donor PTz BI-O to fabricate all-polymer solar cells（all-PSCs）, which displayed impressive power conversion efficiencies up to 8.00%. The improved photovoltaic performances of all-PSCs based on these newly developed starburst acceptors can be ascribed to the combination of increased charge carrier mobilities, reduced bimolecular recombination, and formation of more favorable film morphology. These findings demonstrate that the construction of starburst polymer acceptors is a feasible strategy for the fabrication of high-performance all-PSCs.

关 键 词：all-polymer solar cells starburst polymer acceptors conjugated polymer naphthalene diimide 

分 类 号：TM914.4[电气工程—电力电子与电力传动]